Remove the Smog Pump?

Mosaic302

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Jun 30, 1997, 3:00:00 AM6/30/97

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I have a 91 LX with the smog pump still attatched. My buddy said that if I
remove it or bypass it with a shorter belt that it'll give me up to 15hp
with no problems what so ever. I do know that the computer will then
become confused and the check engine light will flash on and off. Are
there any long term side effects with doing this? Will I really get all
the horsepower gain? Any info wiould be helpful.
Thanks
Phil
14.2 @ 90 on radials

Dan

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Jul 1, 1997, 3:00:00 AM7/1/97

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Mosaic302 <mosa...@aol.com> wrote in article
<19970630211...@ladder01.news.aol.com>...

I bypassed my smog pump about a year ago and just about a month ago I
removed it. I do have the check engine light come on from time to time but
I don't think it is caused by removing the air pump. I tend to get really
wacked out codes and I think that it is from something else. I don't know
about how much horsepower you get but when I bypassed it I turned it by
hand and it was really hard to do. It must rob a substantial amount of
power( ie. 10-15 horsepower). One other thing, I get the check engine
light more when it is cold out like in the winter. This summer so far I
have seen the light come on about 3 times and thats it. Don't know what
the connection is but my car runs fine.

Dan
89 LX conv't
>

David A. Lyons

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Jul 1, 1997, 3:00:00 AM7/1/97

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Mosaic302 wrote:
>
> I have a 91 LX with the smog pump still attatched. My buddy said that
> if I remove it or bypass it with a shorter belt that it'll give me up
> to 15hp with no problems what so ever. I do know that the computer
> will then become confused and the check engine light will flash on and
> off. Are there any long term side effects with doing this? Will I
> really get all the horsepower gain? Any info wiould be helpful.

I've heard that at full throttle the smog pumps "shuts off", and is no
more of a load than a simple "idler" pulley.

--
David Lyons
mailto:lyo...@alf.dec.com
mailto:lyo...@mindspring.com
http://www.mindspring.com/~lyonsd

Stang88LX

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Jul 2, 1997, 3:00:00 AM7/2/97

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take the belt off and spin the smog pump pulley.... spins freely huh
so that means no restriction so there is no GAIN bypassing it.
now try to spin the power steeering pulley......AH HA.,,, if anything
bypass that!

only reason i bypassed the smog pump is because it was making my car
backfire somehow

Mark A. Willette

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Jul 2, 1997, 3:00:00 AM7/2/97

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On 2 Jul 1997 06:34:09 GMT, stan...@aol.com (Stang88LX) wrote:

>take the belt off and spin the smog pump pulley.... spins freely huh
>so that means no restriction so there is no GAIN bypassing it.

I have never owned a smog pump that spins freely. Mine pumps air out
the hole in the side of it, which consumes some power. (No such thing
as a free lunch.) I need to get one like yours...where can I find
one? Seriously though, the Motorsport air pump eliminator pulley will
be the next replacement.

>only reason i bypassed the smog pump is because it was making my car
>backfire somehow

One of your emissions bypass valves probably failed. My roommate's
'84 had that problem anyway. With the '84 emissions setup you could
use a vacuum pump to test the valves...I don't know what the EFI setup
is like though.

-Mark
'79 Mustang
http://www.intex.net/~gug/mustangs/real.html

Stang88LX

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Jul 2, 1997, 3:00:00 AM7/2/97

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my car is WAY FAR from being emission legal
no vaccum lines are hooked up and its Speed density
maybe that explains the CONSTANT rolling idle!??? Hmmmmmmm